Aerobic heart rate is generally defined as the target heart rate necessary to gain aerobic benefits from exercise. Exercisers who successfully attempt to raise their heart rates into the aerobic zone during exercise can build respiratory and cardiovascular endurance while making their hearts larger and stronger. Aerobic heart rate is usually defined as being 70 to 80 percent of one's maximum heart rate. Simple mathematic formulas can be used to estimate one's individual aerobic heart rate.
There are two common ways to calculate target aerobic heart rate. The formula (220-age of exerciser) X desired percentage of maximum heart rate is considered especially useful for people who exercise infrequently or have just begun aerobic exercise. For a 25-year-old person, the formula would generally look something like this: (220-25) X 0.7 = 122.5 and (220-25) X .8 = 156. This person would therefore need to reach and maintain a minimum heart rate of between 123 and 156 beats per minute during exercise in order to enjoy significant aerobic benefits, including increased endurance, a stronger heart, and body fat loss.
Increased aerobic endurance often leads to a decrease in resting heart rate, so people who exercise for endurance regularly may want to use a different formula that takes resting heart rate into account. Most experts believe that the best time to measure resting heart rate is first thing in the morning, before any caffeine is consumed and before any exercise is performed. Heart rate is usually measured in beats per minute. Resting heart rate can be determined by counting the number of times one's heart beats during a 60-second period of time. The carotid artery in the neck is most often used for this purpose.
Once resting heart rate has been calculated, the following formula can be applied to calculate aerobic heart rate: (220-age of exerciser-exerciser's resting heart rate) X desired percentage of maximum heart rate + exerciser's resting heart rate. For the same 25 year old person with a resting heart heart rate of 70 beats per minute, the formula would generally look like this: (220-25-70) X 0.7 + 70 = 157.5 and (220-25-70) X 0.8 + 70 = 170. According to this formula, target aerobic heart rate is between 158 and 170. This formula often gives a different set of target heart rate numbers, because this formula considers the present aerobic condition of the exerciser, as indicated by resting heart rate.